Process to make pmr writer with leading edge shield (les) and leading edge taper (let)

ABSTRACT

Methods for fabrication of leading edge shields and tapered magnetic poles with a tapered leading edge are provided. The leading edge shield may be formed by utilizing a CMP stop layer. The CMP stop layer may aid in preventing over polishing of the magnetic material. For the tapered magnetic poles with a tapered leading edge, a magnetic material is deposited on a planarized surface, a patterned resist material is formed, and exposed magnetic material is etched to form at least one tapered surface of the magnetic material.

BACKGROUND OF THE INVENTION

1. Field of the Invention

Embodiments of the present invention generally relate to leading edgeshields and magnetic heads for data recording, and more particularly toa method for manufacturing a leading edge shield and a perpendicularmagnetic write head having a tapered write pole.

2. Description of the Related Art

The heart of a computer's long term memory is an assembly that isreferred to as a magnetic disk drive. The magnetic disk drive includes arotating magnetic disk, write and read heads that are suspended by asuspension arm adjacent to a surface of the rotating magnetic disk, andan actuator that swings the suspension arm to place the read and writeheads over selected circular tracks on the rotating disk. The read andwrite heads are directly located on a slider that has an air bearingsurface (ABS). The suspension arm biases the slider toward the surfaceof the disk, and when the disk rotates, air adjacent to the disk movesalong with the surface of the disk. The slider flies over the surface ofthe disk on a cushion of this moving air. When the slider rides on theair bearing, the write and read heads are employed for writing magnetictransitions to and reading magnetic transitions from the rotating disk.The read and write heads are connected to processing circuitry thatoperates according to a computer program to implement the writing andreading functions.

The write head has traditionally included a coil layer embedded infirst, second and third insulation layers (insulation stack), theinsulation stack being sandwiched between first and second pole piecelayers. A gap is formed between the first and second pole piece layersby a gap layer at an air bearing surface (ABS) of the write head and thepole piece layers are connected at a back gap. Current conducted to thecoil layer induces a magnetic flux in the pole pieces which causes amagnetic field to fringe out at a write gap at the ABS for the purposeof writing the aforementioned magnetic transitions in tracks on themoving media, such as in circular tracks on the aforementioned rotatingdisk.

In recent read head designs, a GMR or TMR sensor has been employed forsensing magnetic fields from the rotating magnetic disk. The sensorincludes a nonmagnetic conductive layer, or barrier layer, sandwichedbetween first and second ferromagnetic layers, referred to as a pinnedlayer and a free layer. First and second leads are connected to thesensor for conducting a sense current there-through. The magnetizationof the pinned layer is pinned perpendicular to the air bearing surface(ABS) and the magnetic moment of the free layer is located parallel tothe ABS, but free to rotate in response to external magnetic fields.

In order to meet the ever increasing demand for improved data rate anddata capacity, researchers have recently been focusing their efforts onthe development of perpendicular recording systems. A traditionallongitudinal recording system, such as one that incorporates the writehead described above, stores data as magnetic bits orientedlongitudinally along a track in the plane of the surface of the magneticdisk. This longitudinal data bit is recorded by a fringing field thatforms between the pair of magnetic poles separated by a write gap.

A perpendicular recording system, by contrast, records data asmagnetizations oriented perpendicular to the plane of the magnetic disk.The magnetic disk has a magnetically soft underlayer covered by a thinmagnetically hard top layer. The perpendicular write head has a writepole with a very small cross section and a return pole having a muchlarger cross section. A strong, highly concentrated magnetic field emitsfrom the write pole in a direction perpendicular to the magnetic disksurface, magnetizing the magnetically hard top layer. The resultingmagnetic flux then travels through the soft underlayer, returning to thereturn pole where it is sufficiently spread out and weak that it willnot erase the signal recorded by the write pole when it passes backthrough the magnetically hard top layer on its way back to the returnpole.

In a perpendicular magnetic recording system, it is desirable tomaximize write field strength and also maximize field gradient. A strongwrite field ensures that a magnetic bit can be recorded in themagnetically hard top layer of the magnetic medium. A high fieldgradient allows for fast magnetic switching of the magnetic field fromthe write pole, thereby increasing the speed with which the magnetictransitions can be recorded.

Some of the problems encountered with perpendicular recording are sidewriting and side erasure to adjacent tracks on the disk. These problemsoccur from leakage and fringing of the magnetic flux from the magneticwrite head. To minimize these effects, one approach is to provide eithera trailing or wrap-around shield on the magnetic write head. Thewrap-around shield head has the main pole surrounded on three sides bythree shields from the air bearing surface view. These shields alloweffective magnetic flux to be provided for writing to the disk, whileavoiding leakage and fringing that can lead to the above-describedproblems. Another solution is to use a slanted pole on the trailing sideof a writer. However, both solutions exhibit limitations as higherrecording area density are sought for current and future products.

SUMMARY OF THE INVENTION

Embodiments of the present invention generally relate to leading edgeshields and magnetic write heads, and more specifically to fabricationof leading edge shields and tapered structures within the magneticheads.

One embodiment of the invention provides a method for fabricating amagnetic head. The method generally comprises providing a substratehaving a first non-magnetic material disposed thereon, a featuredefinition formed in the first non-magnetic material, and a firstmagnetic material disposed in the feature definition, wherein thefeature definition has a trapezoidal cross-sectional shape and the firstmagnetic material forms a planar surface in the feature definition,depositing a second magnetic material on the planar surface, forming apatterned resist material on the second magnetic material to expose aportion of the second magnetic material, etching the exposed secondmagnetic material to form at least one tapered surface of the secondmagnetic material, removing the patterned resist material, depositing asecond non-magnetic material on the second magnetic material having atleast one tapered surface, depositing a third non-magnetic material onthe second non-magnetic material, and planarizing the secondnon-magnetic material and the third non-magnetic material to the surfaceof the second non-magnetic material.

Another embodiment of the invention provides a method for fabricating amagnetic head. The method generally comprises forming a magnetic leadingedge shield in a substrate surface, the leading edge shield having aplanar surface that tapers from the planar surface to an underlyingportion of the substrate surface, depositing a magnetic leading edgematerial on the leading edge shield material, patterning a resistmaterial on the magnetic leading edge material, wherein the patternedresist material exposes a portion of the magnetic leading edge material,etching the exposed portion of the magnetic leading edge material usingthe patterned resist material as a mask, wherein the etching removes theexposed portion of the magnetic leading edge material to form one ormore tapered surfaces, depositing an etch stop layer over the magneticleading edge material having one or more tapered surfaces, depositing abulk fill material over the etch stop layer, and planarizing the bulkfill material to the etch stop layer.

Another embodiment of the invention provides one embodiment of amagnetic head. The magnetic head generally comprises a non-magnetic,electrically insulating material, a leading edge shield formed on thenon-magnetic, electrically insulating material, a leading edge taperformed on the leading edge shield with the leading edge taper taperingaway from an air bearing surface (ABS) end of the magnetic head, a writepole formed on the leading edge taper and the leading edge shield andhaving a tapered region having a tapered trailing edge portion and anon-tapered region, wherein a thickness of the tapered region of thewrite pole increases in a direction away from an air bearing surface(ABS) end of the magnetic head, a first non-magnetic layer formed on thenon-tapered region of the magnetic pole, a non-magnetic bump layerformed on the tapered region, wherein the non-magnetic bump layer isadjacent to a sidewall portion of the first non-magnetic layer, a secondnon-magnetic layer formed on a portion of the tapered region of thewrite pole that is not covered by the bump layer, and a trailing edgeshield formed on the tapered region, wherein the trailing edge shield isseparated from the write pole by at least the second non-magnetic layerand the bump layer.

In another embodiment, method of fabricating a leading edge shield isdisclosed. The method includes depositing a chemical mechanicalpolishing stop layer over a substrate, forming a photoresist mask overthe chemical mechanical polishing stop layer, and etching at least aportion of the chemical mechanical polishing stop layer and at least aportion of the substrate to form a feature definition. The method alsoincludes removing the photoresist mask to expose the chemical mechanicalpolishing stop layer, depositing leading edge shield material into thefeature definition and over the exposed chemical mechanical polishingstop layer, chemical mechanical polishing the leading edge shieldmaterial to expose the chemical mechanical polishing stop layer, andremoving the chemical mechanical polishing stop layer.

In another embodiment, a method of fabricating a leading edge shield isdisclosed. The method includes forming a photoresist mask over asubstrate, etching at least a portion of the substrate to form a featuredefinition, and removing the photoresist mask to expose the substrate.The method also includes depositing a chemical mechanical polishing stoplayer over the substrate and in the feature definition, depositingleading edge shield material over the chemical mechanical polishing stoplayer, chemical mechanical polishing the leading edge shield material toexpose at least a portion of the chemical mechanical polishing stoplayer, and removing the exposed portion of the chemical mechanicalpolishing stop layer.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above recited features of the presentinvention can be understood in detail, a more particular description ofthe invention, briefly summarized above, may be had by reference toembodiments, some of which are illustrated in the appended drawings. Itis to be noted, however, that the appended drawings illustrate onlytypical embodiments of this invention and are therefore not to beconsidered limiting of its scope, for the invention may admit to otherequally effective embodiments.

FIG. 1 is a schematic illustration of a disk drive system in which theinvention might be embodied;

FIG. 2 is an air bearing surface (ABS) view of a slider, taken from line2-2 of FIG. 1, illustrating the location of a magnetic head thereon;

FIG. 3 is a cross sectional view of a magnetic write head according toan embodiment of the present invention;

FIG. 4A is a cross sectional view of a pole tip region of a write headaccording to an alternate embodiment of the invention;

FIG. 4B is an air bearing surface (ABS) view of the write head of FIG.4A, as viewed from line B-B of FIG. 4A;

FIGS. 5A-5G illustrate an exemplary method for forming a leading edgeshield and leading edge taper for a flared write pole according to anembodiment of the invention;

FIGS. 6A-6E illustrate one embodiment of a method for forming a leadingedge shield according to an embodiment of the invention;

FIGS. 7A-7E illustrate another embodiment of a method for forming aleading edge shield according to an embodiment of the invention; and

FIGS. 8A-8F illustrate one embodiment of a method for forming the mainpole in addition to the write pole according to an embodiment of theinvention.

To facilitate understanding, identical reference numerals have beenused, where possible, to designate identical elements that are common tothe figures. It is contemplated that elements disclosed in oneembodiment may be beneficially utilized on other embodiments withoutspecific recitation.

DETAILED DESCRIPTION

In the following, reference is made to embodiments of the invention.However, it should be understood that the invention is not limited tospecific described embodiments. Instead, any combination of thefollowing features and elements, whether related to differentembodiments or not, is contemplated to implement and practice theinvention. Furthermore, although embodiments of the invention mayachieve advantages over other possible solutions and/or over the priorart, whether or not a particular advantage is achieved by a givenembodiment is not limiting of the invention. Thus, the followingaspects, features, embodiments and advantages are merely illustrativeand are not considered elements or limitations of the appended claimsexcept where explicitly recited in a claim(s). Likewise, reference to“the invention” shall not be construed as a generalization of anyinventive subject matter disclosed herein and shall not be considered tobe an element or limitation of the appended claims except whereexplicitly recited in a claim(s).

Embodiments of the invention are generally related to leading edgeshields and magnetic write heads, and more specifically to methods forfabrication of leading edge shields and tapered magnetic poles. Amagnetic pole may have a plurality of tapered surfaces at or near an airbearing surface (ABS), wherein a thickness of the write pole increasesin a direction away from the ABS.

Referring now to FIG. 1, there is shown a disk drive 100 embodying thisinvention. As shown in FIG. 1, at least one rotatable magnetic disk 112is supported on a spindle 114 and rotated by a disk drive motor 118. Themagnetic recording on each disk is in the form of annular patterns ofconcentric data tracks (not shown) on the magnetic disk 112.

At least one slider 113 is positioned near the magnetic disk 112, eachslider 113 supporting one or more magnetic head assemblies 121. As themagnetic disk rotates, the slider 113 moves radially in and out over thedisk surface 122 so that the magnetic head assembly 121 may accessdifferent tracks of the magnetic disk where desired data are written.Each slider 113 is attached to an actuator arm 119 by way of asuspension 115. The suspension 115 provides a slight spring force whichbiases slider 113 against the disk surface 122. Each actuator arm 119 isattached to an actuator means 127. The actuator means 127 as shown inFIG. 1 may be a voice coil motor (VCM). The VCM comprises a coil movablewithin a fixed magnetic field, the direction and speed of the coilmovements being controlled by the motor current signals supplied bycontroller 129.

During operation of the disk storage system, the rotation of themagnetic disk 112 generates an air bearing between the slider 113 andthe disk surface 122 which exerts an upward force or lift on the slider.The air bearing thus counter-balances the slight spring force ofsuspension 115 and supports slider 113 off and slightly above the disksurface by a small, substantially constant spacing during normaloperation.

The various components of the disk storage system are controlled inoperation by control signals generated by control unit 129, such asaccess control signals and internal clock signals. Typically, thecontrol unit 129 comprises logic control circuits, storage means and amicroprocessor. The control unit 129 generates control signals tocontrol various system operations such as drive motor control signals online 123 and head position and seek control signals on line 128. Thecontrol signals on line 128 provide the desired current profiles tooptimally move and position slider 113 to the desired data track on disk112. Write and read signals are communicated to and from write and readheads 121 by way of recording channel 125.

With reference to FIG. 2, the orientation of the magnetic head 121 in aslider 113 can be seen in more detail. FIG. 2 is an ABS view of theslider 113, and as can be seen the magnetic head including an inductivewrite head and a read sensor, is located at a trailing edge of theslider. The above description of a typical magnetic disk storage systemand the accompanying illustration of FIG. 1 are for representationpurposes only. It should be apparent that disk storage systems maycontain a large number of disks and actuators, and each actuator maysupport a number of sliders.

With reference now to FIG. 3, the invention can be embodied in amagnetic head 302 having a tapered write pole and a tapered leadingedge. A non-magnetic bump may also be included in the embodiment asshown in FIG. 3. The magnetic write head 302 includes a magnetic writepole 304 and a magnetic return pole 306. A magnetic back gap layer 308and magnetic shaping layer 310 magnetically connect the return pole 306with the write pole 304 at a location removed from an air bearingsurface ABS. The magnetic write pole is further defined by a leadingedge shield 307 and a leading edge taper 305.

An electrically conductive, non-magnetic write coil 318 passes betweenthe write pole 304 and the return pole 306 and may also pass above thewrite pole 304. The write coil 318 can sit on top of a non-magnetic,electrically insulating material 322 and is also embedded in anon-magnetic, electrically insulating material 320 such as aluminaand/or a hard baked photoresist.

During operation, an electrical current flowing through the coil 318induces a magnetic field the results in a magnetic flux flowing throughthe write pole 304. This causes a magnetic field to be emitted from thewrite pole 304 toward a magnetic medium such as the magnetic medium 122shown in FIG. 1. This magnetic write field flows through the medium toreturn to the return pole 306 which has a sufficiently large crosssection that it does not erase the magnetic bit written by the writepole 304.

In order to increase the write field gradient (and thereby increaseswitching speed), the write head 302 also includes a magnetic leadingshield 307 having a leading edge taper 305. Additionally, in order toincrease the write field gradient (and thereby increase switchingspeed), the write head 302 also includes a magnetic trailing shield 312.This trailing shield 312 is separated from the write pole 304 by atrailing gap layer 332. The write pole 304 may also be connected with atrailing return pole 316 that connects the trailing shield 312 with theback portion of the write head 302, such as the back portion of theshaping layer 310.

In some embodiments, the first width of the write head is between 20 nmand 150 nm and can taper away from the air bearing surface (ABS) at anangle a with respect to a plane parallel to the ABS surface. In oneembodiment a is between about 30° and about 60°.

With reference now to FIGS. 4A and 4B, a pole tip portion of a writehead according to one embodiment of the invention is shown. As shown inFIG. 4A, the write head 402 includes a write pole 404 that has a taperedtrailing edge portion 406 (similar to the previously describedembodiment), but which also has a tapered leading edge portion 408.Having both tapered trailing and leading edges further optimizes theperformance of the write head 402 by focusing magnetic flux to the tipof the write pole 404 while avoiding magnetic saturation of the writepole 404.

The write head 402 has a leading edge shield 410, a magnetic leadingedge shield with a leading edge taper 411 as well as a trailing edgeshield 412, and a trailing magnetic shield. The leading edge shield 410is separated from the write pole 404 by a leading gap distance 414, andthe trailing edge shield 412 is separated from the trailing edge of thewrite pole 404 by a trailing gap distance 416, the leading gap distance414 being significantly larger than the trailing gap distance 416 so asto prevent magnetic write field from being drawn toward the leading edgeshield 410 during operation. The leading gap distance 414 is preferablyat least twice the trailing gap distance 416, and is more preferablyabout four times the trailing gap distance 416. In one example, theleading gap distance 414 can be about 100 μm, whereas the trailing gapdistance 416 can be about 25 μm.

The leading edge shield 410 is separated from the write pole 404 byfirst and second nonmagnetic layers 418, 420. The first layer 418 can beconstructed of a material such as chromium (Cr) or an alloy ofnickel-chromium (NiCr). The second layer 420 can be constructed of amaterial such as ruthenium (Ru).

The write head also includes a non-magnetic spacer layer 422 which canbe constructed of a material such as NiCr and can have a thickness of50-200 μm. The non-magnetic spacer layer has a front edge 424 that islocated a desired distance from the air bearing surface ABS. Anon-magnetic bump 426, constructed of a material such as alumina Al₂O₃is formed at the front edge of the non-magnetic spacer layer 422,extending over a portion of the tapered trailing edge 406 of the writepole 404. The non-magnetic spacer layer 422 and non-magnetic bump layer426 provide additional spacing between the trailing edge shield 412 andthe write pole 404 and also optimize the profile of this spacing byproviding a smooth transition to this additional spacing.

The write head also includes a non-magnetic trailing gap layer 428 thatseparates the trailing edge shield 412 from the write pole 404 and whichmay also extend over the non-magnetic bump 426 and non-magnetic spacerlayer 422. The nonmagnetic trailing gap layer can be constructed of amaterial such as Ruthenium. In addition, non-magnetic, electricallyinsulating fill layers 430 may be provided behind the shields 410, 412,although structures could be included in these regions as well. Also, ahigh magnetic moment seed layer 432 such as cobalt-iron (CoFe) may beincluded at the bottom of the trailing edge shield 412 to improve theperformance of the trailing shield.

FIG. 4B shows the write head 402 as viewed from the air bearing surface.As can be seen in FIG. 4B, the trailing edge shield 412 extends downwardbeyond the sides of the write pole to form side shielding portions 452,454. For this reason, the trailing edge shield 412 can also be referredto as a “wrap-around” shield. Write head also includes non-magneticinsulating side fill layers 456, 458 that (for reasons that will becomeapparent below) are preferably constructed of a reaction ion etchable(RIEable) material such as SiO₂ or alumina. It also can be seen, thatthe non-magnetic side fill layers have substantially vertical outersides, and that the layer 420 discussed above with reference to FIG. 4A,also extends up the sides of the write head (also for reasons that willbecome apparent below). The thickness of the layers 420, 456, 428, 432define the side gap distance 460.

It can be seen in FIG. 4B, that the layers 418 and 428 extend betweenthe trailing edge shield 412 and the leading edge shield 410 so that theshields 412, 410 do not contact one another. In another embodiment ofthe invention, the layers 418 and 428 terminate at some point away fromthe write pole 404 so that the trailing edge shield 412 and leading edgeshield 410 make magnetic contact at regions beyond the layers 418,428.This embodiment can improve the performance of the trailing edge shield412 by improving the flow of magnetic flux from the trailing edge shield412.

FIGS. 5A through 8G describe embodiments of methods for manufacturing amagnetic write head according to the various embodiments described abovewith reference to FIG. 3 and FIGS. 4A-4B.

FIGS. 5A-5G illustrate exemplary steps performed during fabrication of aleading edge taper of a write pole according to an embodiment of theinvention.

As illustrated in FIG. 5A, in one embodiment, fabrication of thestructure may begin by providing a substrate material 500. The substratematerial 500 may be composed of a non-magnetic material, such asaluminum oxide (Al₂O₃), also known as “alumina”. While not shown in theFigures, the substrate material 500 may include one or more othercomponents of a magnetic head, e.g., a read head and one or morecomponents of a write head already formed therein. Additionally, whilenot shown, the substrate material 500 may include a reaction ionetchable stop layer (310 above) disposed therein to form the bottom ofany feature definition. Substrate material 500 may correspond toinsulating material 320 of FIG. 3. In an alternative embodiment, thesubstrate material 500 may be a magnetic material as described herein.

A layer of material 510 that is resistant to reactive ion etching (RIE),a RIE stop layer, is deposited over the substrate. The RIE stop layer510 can be a non-magnetic material such as tantalum (Ta), tantalumnitride (TaN), titanium (Ti), titanium nitride (TiN), chromium (Cr), analloy of nickel and chromium (NiCr), ruthenium (Ru), and combinationsthereof, or laminated layers of these materials.

A fill layer 520 is deposited over the material layer 510. The filllayer 520 may be a reactive ion etchable (RIEable) material, forexample, alumina (Al₂O₃), silicon dioxide (SiO₂), silicon nitride, andis deposited at least as thick as the desired thickness of a desiredwrite pole thickness, as will become apparent below.

A feature definition 535 may be formed in the reactive ion etchablematerial (RIEable) of the fill layer 520 by a reactive ion etching (RIE)process, such as ion beam etching (IBE). The reactive ion etching (RIE)process is preferably performed at one or more angles relative to normalto form the fill layer 520 with the feature definition 535 havingtapered side walls 537. The one or more angles are from 10° to 60°relative to normal and are angled outward from the bottom of the featuredefinition to the top of the feature definition. Such a structureprovides for a tapered structure from the surface into the material 520,which can form a trapezoidal shape.

A non-magnetic material 530, which may be a polishing stop material asdescribed in FIGS. 6A-6E, may be deposited by a conformal depositionprocess such as atomic layer deposition. This non-magnetic material 530may be a non-magnetic material including tantalum (Ta), tantalum nitride(TaN), titanium (Ti), titanium nitride (TiN), chromium (Cr), an alloy ofnickel and chromium (NiCr), ruthenium (Ru), and combinations thereof, orlaminated layers of these materials, and may be deposited to asufficient thickness to advantageously reduce the width of the trench inorder to shrink the track width of the yet to be formed write pole.

Then, a magnetic material 540, such as cobalt-iron (CoFe) orcobalt-nickel-iron (CoNiFe), may be deposited, such as byelectroplating, into the feature definition 535 formed in the fill layer520. The magnetic material 540 forms the leading edge shield material ofthe structure for a later main pole structure. A chemical mechanicalpolishing (CMP) process may be performed to planarize the magnetic layer540, leaving a structure as shown in FIGS. 5A, with a write polematerial 540 in the feature definition 535. An ion milling may then alsobe performed to remove portions of the non-magnetic layer 535 that mayextend over the fill layer 520.

Referring to FIG. 5B, a magnetic material 550, which will be a lead edgetaper material, is then conformally deposited, such as by a sputteringprocess, on the planarized surface of the fill layer 520, non-magneticmaterial 530, and magnetic material 540. The magnetic material 550 is ametal alloy selected from the group of nickel-iron (NiFe), cobalt-iron(CoFe), cobalt-nickel-iron (CoNiFe), and combinations thereof. Themagnetic material 550 may the same material or a different material fromthe magnetic layer 540. The magnetic material 550 may be deposited by asputtering process, and may be deposited to a thickness from about 500 Åto about 1500 Å, for example about 1100 Å. A photoresist/resist material560 is then deposited and patterned on the magnetic material 550.

Referring to FIG. 5C, an ion milling process or a reactive ion etchprocess, such as a ion beam etching (IBE) process, may be performed toremove portions of the magnetic layer 550 exposed by the patternedphotoresist/resist material 560. The ion milling is performed to removea portion of the magnetic material layer 550 at a preferred angle,thereby allowing the formation of a tapered surface 555 on the magneticmaterial layer 550. Additionally, the magnetic layer may be ion milledto provide for the tapered material having the end of the taper portionsbe within the horizontal surface bounds of the underlying magneticmaterial 540 as shown in FIG. 5C. In one embodiment, the magneticmaterial layer 550 has a tapered portions coupled only to the underlyingmagnetic material 540 on the substrate surface.

The ion milling is performed at one or more angles relative to normal,such that shadowing from the patterned photoresist/resist layer 560causes the tapered surface to form an angle from 10 to 60 degrees, suchas from 20 to 40 degrees, for example, about 30 degrees with respect toa plane that is parallel with the surfaces of the as deposited layers.The tapered structure forms the leading edge taper structure. As shownon the Figures, the leading edge taper may have more than one taperedside, and each side may have the same or substantially the same angles.If any non-magnetic material 550 was disposed on the surface of thelayers (not shown), the non-magnetic material 530 may be removed withthe ion milling process.

Referring to FIG. 5D, the patterned photoresist/resist material 560 isthen removed from the magnetic layer 550. The patternedphotoresist/resist material 560 may be removed by a liftoff or ashingprocess.

Referring to FIG. 5E, a non-magnetic layer 570 is conformally depositedover the magnetic material layer 550 and the exposed surfaces of thefill layer 520, non-magnetic material 530, and magnetic material 540.The non-magnetic layer 570 may be a reactive ion etching (RIE) stoplayer and may be a non-magnetic material including tantalum (Ta),tantalum nitride (TaN), titanium (Ti), titanium nitride (TiN), chromium(Cr), an alloy of nickel and chromium (NiCr) ruthenium (Ru), andcombinations thereof, or laminated layers of these materials. Thenon-magnetic layer 570 may be deposited to a thickness of 40-60 μm orabout 50 μm.

Referring to FIG. 5F, a bulk layer 580 of a non-magnetic material, suchas alumina, may be deposited over the conformal non-magnetic RIE stoplayer 570.

The bulk layer 580 (and optionally, the non-magnetic RIE stop layer 570)may then be planarized. The substrate material 500 and bulk layer 580may be of the same material, and may comprises a material selected fromthe group of alumina (Al₂O₃), silicon oxide, silicon nitride, ancombinations thereof, amongst other dielectric materials. The formedstructure may then provide for main pole processing.

FIG. 5G, illustrates the layering structure after the air bearingsurface process which shows the leading edge shield portion 340 and theleading edge taper portion 355 containing the ABS allowing for theformation of the write pole with a leading tapered surface as shown inFIG. 3.

The structure formed in FIG. 5A, may be formed by several differentprocesses, of which two embodiments can be described as follows withreference to FIGS. 6A-6E and FIGS. 7A-7E, respectively.

One manner to form the leading edge shield comprises depositing a seedlayer over a substrate. The seed layer may be deposited by conventionaldeposition techniques such as electroplating or sputtering. Aphotoresist mask is then formed which leaves select areas of the seedlayer exposed. The magnetic material is then deposited onto the exposedareas of the seed layer. The mask may then be removed, as well as theexposed seed layer that underlies the mask. The removal may occurutilizing ion beam milling to expose the underlying substrate. A layerof Al₂O₃ may then be formed over the exposed surfaces which includeportions of the substrate and the magnetic material. The Al₂O₃ may thenbe planarized back using a CMP process to expose the magnetic material,which is also polished at least partially. The process flow is simple,but can not achieve the desired uniformity for the preferred 0.1 to 0.3micron thickness of the leading edge shield and hence, has nomanufacturability. In contrast, the process flow discussed below inregards to FIGS. 6A-6E includes depositing a CMP stop layer, photopattern, etch, refill, CMP and light mill to provide a better leadingedge shield thickness mean and uniformity control. The process flowdiscussed below in regards to FIGS. 7A-7E involves etching, refillingwith a stop layer and leading edge shield material, then CMP and lightion beam etching. The process flow for FIGS. 6A-6E will leave no processsignature of the CMP stop layer while the process flow for FIGS. 7A-7Ewill have the process signature of a CMP stop layer. The leading edgeshield, for both FIGS. 6A-6E and FIGS. 7A-7E are fabricated after thereader is completed. The leading edge shield is fabricated with a throatheight length ranging from about 0.2 microns to about 0.3 microns. Thethickness of the leading edge shield is between about 0.1 microns andabout 0.3 microns. The magnetic material for the leading edge shield maycomprise soft magnetic materials such as NiFe, CoNiFe, and CoFe.

Referring to FIGS. 6A-6E, the structure of FIG. 5A may be formed byfirst providing a substrate material 600. The substrate material 600 maybe composed of a non-magnetic material, such as aluminum oxide (Al₂O₃),also know as “alumina”. While not shown in the Figures, the substratematerial 600 may include one or more other components of a magnetichead, e.g., a read head and one or more components of a write headalready formed therein. Additionally, while not shown, the substratematerial 600 may include a reaction ion etchable layer stop layer (310above) disposed therein to form the bottom of any feature definition.Substrate material 600 may correspond to insulating material 320 of FIG.3. In an alternative embodiment, the substrate material 600 may be amagnetic material as described herein.

A layer of material 610 that is resistant to chemical mechanicalpolishing (CMP), a CMP resistance material (or CMP stop layer), isdeposited over the substrate. The CMP resistance material 610 may be amaterial selected from the group consisting of iridium (Ir), ruthenium(Ru), Rhodium (Rh), tantalum (Ta), and combinations thereof, and ispreferably a non-magnetic material. The CMP resistance material 610 maybe deposited to a thickness from 100 Å to 500 Å. A photoresist material620 is then deposited and patterned on the CMP resistance material 610.

Referring to FIG. 6B, a feature definition 625 may be formed in thesubstrate material 600 by reactive ion etching (RIE) or ion beam etching(IBE) the exposed CMP resistance material 610 and the underlyingsubstrate material 600. The reactive ion etch process is preferablyperformed at one or more angles relative to normal to form the featuredefinition 625 having tapered side walls 627. The one or more angles arefrom 10° to 60° relative to normal and are angled outward from thebottom of the feature definition to the top of the feature definition.The photoresist/resist material 620 is also removed after the etchingprocess, such as by a liftoff or ashing process. The feature definitionis formed having a depth (or thickness) from 0.1 μm to 0.3 μm.

A magnetic material 630, such as cobalt-iron (CoFe) ofcobalt-nickel-iron (CoNiFe), may be deposited on the CMP stop layer 610and into the feature definition 625 formed in the substrate material 600as shown in FIG. 6C. The magnetic material 630 may be deposited by aplating process, such as electroplating, or a physical vapor deposition(sputtering) process.

A planarization process, such as by a chemical mechanical polishing(CMP) process, may be performed to remove the magnetic layer 630deposited over the CMP stop layer 610 and planarize the magnetic layer630 to the CMP resistance material 610, leaving a structure shown inFIG. 6D, which is in essence a leading edge shield formed in the featuredefinition 625.

An ion milling, such as by a light ion beam etching process (IBE) orsputter etching process may then also be performed to remove portions ofthe CMP resistance material 610 still remaining after the planarizationprocess as shown in FIG. 6E. The ion milling can be skipped if a LETprocess is used further down the line. The ion milling may removebetween about 100 Angstroms and about 500 Angstroms.

Referring to FIGS. 7A-7E, the structure may be formed by first providinga substrate material 700. The substrate material 700 may be composed ofa non-magnetic material, such as Aluminum Oxide (Al₂O₃), also know as“alumina”. While not shown in the figures, the substrate material 700may include one or more other components of a magnetic head, e.g., aread head and one or more components of a write head already formedtherein. A photoresist/resist material 720 is then deposited andpatterned on the substrate material 700. Additionally, while not shown,the substrate material 700 may include a reaction ion etchable layerstop layer (310 above) disposed therein to form the bottom of anyfeature definition. Substrate material 700 may correspond to insulatingmaterial 320 of FIG. 3. In an alternative embodiment, the substratematerial 700 may be a magnetic material as described herein.

Referring to FIG. 7B, a feature definition 725 may be formed in thesubstrate material 700 by reactive ion etching (RIE) or ion beam etching(IBM) the exposed substrate material 700. The reactive ion etch processis preferably performed at one or more angles relative to normal to formthe feature definition 725 having tapered side walls 727. The one ormore angles are from 10° to 60° relative to normal and are angledoutward from the bottom of the feature definition 725 to the top of thefeature definition 725. The feature definition 725 is formed having adepth (or thickness) from 0.1 μm to 0.3 μm. The photoresist/resistmaterial 720 is also removed after the etching process, such as by aliftoff or ashing process.

Referring to FIG. 7C, a layer of material that is resistant to chemicalmechanical polishing (CMP), a CMP resistance material 710 (or CMP stoplayer), is deposited over the substrate and in the feature definitionconformally. The CMP resistance material 710 may be a material selectedfrom the group consisting of iridium (Ir), ruthenium (Ru), Rhodium (Rh),tantalum (Ta), and combinations thereof, and is preferably anon-magnetic material. The CMP resistance material 710 may be sputterdeposited to a thickness from 100 Å to 500 Å.

A magnetic material 730, such as cobalt-iron (CoFe) orcobalt-nickel-iron (CoNiFe), may be deposited onto the CMP resistancematerial 710 and into the feature definition 725 formed in the substratematerial 700 as shown in FIG. 7C. The magnetic material 730 may bedeposited by a plating process, such as electroplating, or a physicalvapor deposition (sputtering) process.

A planarization process, such as by a chemical mechanical polishing(CMP) process, may be performed to remove and planarize the magneticlayer 730 to the CMP resistance material 710, leaving a structure shownin FIG. 7D, which is in essence a leading edge shield formed in thefeature definition 725.

An ion milling, such as by a light ion beam etching process (IBE) maythen also be performed to remove portions of the CMP resistance material710 still remaining after the planarization process as shown in FIG. 7E.

The process flows shown in FIGS. 6A-6E and 7A-7E are comparable. Theprocess flow in FIGS. 6A-6E will leave no process signature of a CMPstop layer while the process flow in FIGS. 7A-7E will have a processsignature of a CMP stop layer. A Cr/NiCr RIE stop layer may be depositedon the leading edge shield after the leading edge shield is completed tomake a perpendicular write head with a four side wrap-around shield butwithout the leading edge taper. After the leading edge shield is done,the leading edge taper can also be built upon the leading edge shield sothat the perpendicular write head will have both a leading edge shieldand a leading edge taper.

Referring to FIGS. 8A-8F, one embodiment of forming a main pole on thewrite material is as follows.

The non-magnetic fill material 380 as shown in FIG. 5F is removed. Anoptional non-magnetic step layer, preferably constructed of NiCr may bedeposited over the non-magnetic layer 570 (non-magnetic reactive ionetching (RIE) stop layer) and the leading edge taper material 555. Thepole material 810 may then be deposited and planarized. The polematerial 810 may comprise a magnetic material as described herein.

A non-magnetic step layer 820, preferably constructed of NiCr isdeposited over the pole material 810. A mask layer and/or aphotoresist/resist layer (not shown) are deposited and patterned overthe non-magnetic step layer 820 and the pole material 810. Thenon-magnetic step layer 820 and the pole material 810 are then etchedand patterned by an ion milling process to form an upper tapered surface825. Any mask or photoresist/resist material are then removed to providethe structure as shown in FIG. 8B.

A layer of non-magnetic material 830, such as alumina, is deposited by aconformal deposition process such as atomic layer deposition or chemicalvapor deposition as shown in FIG. 8C.

Then, an ion milling is performed to preferentially remove horizontallydisposed portions of the alumina layer, leaving an alumina bump 835 atthe front edge of the non-magnetic step layer 820. A layer ofnon-magnetic material 840 is deposited to a thickness to define adesired trailing gap thickness as shown in FIG. 8D. The trailing gaplayer 840 can be constructed of ruthenium and other non-magneticmaterials. A non-magnetic, electrically insulating material 860, such asalumina 860, may then be deposited on the trailing gap layer 840.

Referring to FIG. 8E, the non-magnetic, electrically insulating material860 may then be etched to expose a portion of the trailing gap layer 840formed from the air bearing surface to a portion along the substantiallyhorizontal portion of the trailing gap layer 840. An optional highmagnetic moment seed layer 850 may be deposited and patterned on theexposed trailing gap layer 840. A trailing shield 870 may be depositedon the high magnetic seed layer 850. The high magnetic moment seed layer850 may be provided at the leading edge of the trailing shield 870 (312)to maximize the performance of the trailing shield.

Additional structures, such as a trailing return pole, additionalnon-magnetic, electrically insulating material, and coils may be formedon the structure to form the head structure. The structure may then beprocessed to form an air bearing surface, as shown by line ABS formedthrough the structure in FIG. 8F to form the structure as shown in FIG.3.

While the foregoing is directed to embodiments of the present invention,other and further embodiments of the invention may be devised withoutdeparting from the basic scope thereof, and the scope thereof isdetermined by the claims that follow.

1. A method of fabricating a leading edge shield, comprising: depositinga chemical mechanical polishing stop layer over a substrate; forming aphotoresist mask over the chemical mechanical polishing stop layer;etching at least a portion of the chemical mechanical polishing stoplayer and at least a portion of the substrate to form a featuredefinition; removing the photoresist mask to expose the chemicalmechanical polishing stop layer; depositing leading edge shield materialinto the feature definition and over the exposed chemical mechanicalpolishing stop layer; chemical mechanical polishing the leading edgeshield material to expose the chemical mechanical polishing stop layer;and removing the chemical mechanical polishing stop layer.
 2. The methodof claim 1, wherein the leading edge shield material comprises amagnetic material.
 3. The method of claim 2, wherein the magneticmaterial is selected from the group consisting of cobalt-iron,cobalt-nickel-iron, and combinations thereof.
 4. The method of claim 3,wherein the chemical mechanical polishing stop layer is selected fromthe group consisting of iridium, ruthenium, rhodium, tantalum, andcombinations thereof
 5. The method of claim 4, wherein the chemicalmechanical polishing stop layer has a thickness of between about 100Angstroms to about 500 Angstroms.
 6. The method of claim 5, wherein theleading edge shield material is deposited by sputtering orelectroplating.
 7. The method of claim 6, wherein the substratecomprises Al₂O₃.
 8. The method of claim 1, wherein the chemicalmechanical polishing stop layer is selected from the group consisting ofiridium, ruthenium, rhodium, tantalum, and combinations thereof
 9. Themethod of claim 1, wherein the chemical mechanical polishing stop layerhas a thickness of between about 100 Angstroms to about 500 Angstroms.10. The method of claim 1, wherein the leading edge shield material isdeposited by sputtering or electroplating.
 11. A method of fabricating aleading edge shield, comprising: forming a photoresist mask over asubstrate; etching at least a portion of the substrate to form a featuredefinition; removing the photoresist mask to expose the substrate;depositing a chemical mechanical polishing stop layer over the substrateand in the feature definition; depositing leading edge shield materialover the chemical mechanical polishing stop layer; chemical mechanicalpolishing the leading edge shield material to expose at least a portionof the chemical mechanical polishing stop layer; and removing theexposed portion of the chemical mechanical polishing stop layer.
 12. Themethod of claim 11, wherein the leading edge shield material comprises amagnetic material.
 13. The method of claim 12, wherein the magneticmaterial is selected from the group consisting of cobalt-iron,cobalt-nickel-iron, and combinations thereof.
 14. The method of claim13, wherein the chemical mechanical polishing stop layer is selectedfrom the group consisting of iridium, ruthenium, rhodium, tantalum, andcombinations thereof
 15. The method of claim 14, wherein the chemicalmechanical polishing stop layer has a thickness of between about 100Angstroms to about 500 Angstroms.
 16. The method of claim 15, whereinthe leading edge shield material is deposited by sputtering orelectroplating.
 17. The method of claim 16, wherein the substratecomprises Al₂O₃.
 18. The method of claim 11, wherein the chemicalmechanical polishing stop layer is selected from the group consisting ofiridium, ruthenium, rhodium, tantalum, and combinations thereof
 19. Themethod of claim 11, wherein the chemical mechanical polishing stop layerhas a thickness of between about 100 Angstroms to about 500 Angstroms.20. The method of claim 11, wherein the leading edge shield material isdeposited by sputtering or electroplating.